MIAMI (CBS4) – Some big changes are coming to some popular, and very powerful, prescription painkillers.

Regulators at the Food and Drug Administration announced Thursday that it will cap the amount of acetaminophen in Vicodin, Percocet and other drugs at 325 milligrams per capsule. The drugs currently on the market contain up to 700 milligrams.

The move comes after thousands of cases of liver damage each year have been linked to the powerful painkillers.

“The amount of acetaminophen in these products has gradually crept up over the years,” said FDA deputy director for new drugs Dr. Sandra Kweder. “If you look at these products 20 to 30 years ago, many did not contain high doses of acetaminophen.”

Kweder says many patients who take prescription painkillers which contain acetaminophen may also take other over the counter drugs like Tylenol and Nyquil, which also contain lower doses of the drug, often confusingly labeled ‘APAP’.

In essence, experts say, the consumers are overdosing on dangerous levels of acetaminophen.

“Acetaminophen is a bit like salt, in that it works so well that people put it in almost everything,” said Erik Gordon, a professor at the University of Michigan’s Ross School of Business who follows the pharmaceutical industry. “But it has the same downside in that at the end of day you have no idea how much is in your system.”

Every year, liver failure due to acetaminophen sends 56,000 people to the hospital, and is also the leading cause of death. Of the 200 people that die from liver failure, the FDA estimates 120 of the deaths are linked to over consumption of acetaminophen.

The FDA says at the lower dosage, the drugs will still be effective. They are working with pharmacies and other medical groups to develop a standard labeling for acetaminophen.